Nested routes are missing the allow header in 405 Method Not Allowed responses

[taylor1791]

Bug Report

Versions

axum v0.5.17
axum-core v0.2.9

Platform

Linux [hostname] 5.15.72 #1-NixOS SMP Wed Oct 5 08:39:44 UTC 2022 x86_64 GNU/Linux

Description

When the server replies with 405 from a nested route, it should include an allow header. As of axum 0.5.17, it does not.

Steps to reproduce:

Run this code:

use axum::{routing::get, Router};

#[tokio::main]
async fn main() {
    let router = Router::new().route("/hello", get(|| async { "Hello, World!" }));
    let app = Router::new().nest("/api", router);

    axum::Server::bind(&"0.0.0.0:3000".parse().unwrap())
        .serve(app.into_make_service())
        .await
        .unwrap();
}

Send a POST request to /api/hello.

$ curl -I -X POST http://localhost:3000/api/hello
HTTP/1.1 405 Method Not Allowed
content-length: 0
date: Sat, 12 Nov 2022 18:53:57 GMT

Observe that the response did not include an allow header.

The code in #731 still contains the reply header, indicating this is specific to .nest.

[taylor1791]

I tried the same code on axum 0.6.0-rc.4 and the allow header is present.

[davidpdrsn]

Good catch! I'm curious why that was but yeah if it's fixed in 0.6 then we are good.

[davidpdrsn]

I think we should add a test for it though. Do you perhaps wanna make a PR?

[taylor1791]

Yes! I would love to.